Automatic moisture extractor for compressed air lines



Nov. 1, 1960 woo s 2,958,394

AUTOMATIC MOISTURE EXTRACTOR FOR COMPRESSED AIR LINES Filed Sept. 23,1957 AUTOMATIC MOISTURE EXTRACTOR FOR COMPRESSED AIR LINES John B.Woodmansee, What Cheer, Iowa (6810 Hague Road, Indianapolis, Ind.)

Filed ept. 23, 1957, Ser. No. 685,543

Claims. (Cl. 183-41) This invention relates to moisture extractors forcompressed air lines, and more particularly to extractors of the typefor automatically separating liquid contaminates and discharging themfrom the system.

One of the objects of this invention is to provide an improved moistureextractor of the character indicated, which is constructed and arrangedfor automatically discharging liquid contaminates separated from the airin the lines when the flow of air through the device is discontinued.

Another object is to provide an improved moisture extractor of thecharacter indicated which is constructed and arranged so as to permitquick and easy assembly and disassembly, and which permits servicingand/or replacement of parts without removal of the device from thelines.

A further object is to provide an improved moisture extractor of thecharacter indicated which is of simple design and construction, composedof relatively few parts, which is highly efiicient in operation, andwhich is economical to manufacture and assemble.

Other objects and advantages of this invention will be apparent from thefollowing description taken in connection with the accompanyingdrawings, in which:

Figure l is a vertical sectional view through the extractor deviceembodying the present invention shown at full scale.

Figure 2 is a view similar to Figure 1, showing the position of thevarious parts while the device is in operation.

Figure 3 is a transverse, sectional view through the device takensubstantially as indicated at line 3-3 on Figure 1.

Moisture extractor devices of the type embodying the present inventionare adapted to a relatively wide field of use, such as in connectionwith various types of air operated tools, paint spray guns, pneumaticcylinders, printing presses, molding machines, carton forming machines,and various other equipment and machines which are intermittentlyoperated. The device embodying the present invention serves toautomatically separate and discharge continuously, liquid contaminates,such as water, oil, or other liquids, from compressed air lines. Whilereference is made to the device being usable in connection withcompressed air lines, it is to be understood that this term is intendedto be broadly interpreted as including steam lines, since the devicefunctions equally satisfactorily for removing water and other liquidcontaminates in steam lines.

The device embodying the present invention comprises a housing A, formedof two main parts, including a body 10, and a bottom member 11. The bodyand bottom members are preferably formed as metallic castings and, whenassembled, define a closed chamber 12. The cross-section of the body, inthe main, is of generally circular cross-section, and the upper portionthereof is formed with a centrally located, downwardly open piston bore14, for communicating with the chamber 12. A

piston 16 is slidably mounted in the bore 14, and is normally urged in adownward direction by a coil spring 18. The body is formed with a fluidinlet opening 20 in direct communication with the chamber 12, and anoutlet opening 22 in direct communication with the piston bore 14. Whenthe device is in an inoperative position with the piston in the positionseen in Figure 1 of the drawings, communication between the chamber 12and the outlet opening 22 is closed. The piston is provided with anequalizing vent opening 24, so that pressure at opposite sides of thepiston is substantially equalized after flow of compressed air throughthe device is shut off, so as to permit the piston to return to aninoperative position, as seen in Figure 1 of the drawing.

The bottom member 11 is formed so as to constitute a sump for collectingliquid contaminates in the system. This bottom member has its outermarginal edge formed as a flange provided with a groove for thereception of a sealing gasket 26, adapted to be compressed against anannular shoulder 28, formed in the bore in the lower end of the body 10.The bore formed in the lower portion of the body 10 is provided with agroove 30, into which is adapted to be projected a O ring 32, fordetachably locking the bottom member 11 in sealed relation to the body10. By virtue of this construction, the parts of the device may bequickly and easily assembled without the use of bolts or screws, and maybe quickly and easily disassembled for servicing or replacement ofparts, without removing the device from the compressed air lines.

The interior or body is provided with a downwardly extending annularshoulder 36, around which is seated the upper marginal edge of acylindrical screen 38. The lower marginal edge of the screen is adaptedto be seated in a recess 40, formed in the bottom member 11, forassisting in confining the screen 38 in position. The purpose of thescreen is to separate and strain out of the fluid in the system, lint,pipe scale and any other solid matter.

Threaded into the bottom of the piston 16 is a hollow stem 42, having anelongated cavity or chamber 44. The lower end of the stem is reduced incross-section, as indicated at 45, thereby defining an annular shoulder46. The reduced portion 45 of the stem is provided with a moistureloading and discharge port 43 in communication with the cavity 44. Thelower or reduced portion 45 of the stem is slidably guided in a sealingdevice mounted in the bottom member 11. The sealing device comprises anassembly including an annular ring 5%, with a groove in which is seateda resilient 0 ring 52, positioned for sealing engagement with saidreduced portion 45 of the stem. The sealing device, comprising the parts50 and 52, is press fitted in a bore formed in the upper surface of thebottom member 11. The bottom member 11 is formed with a depending nipple'54, having an internal bore '56 of a size so as to provide clearancearound the reduced stem portion 45 for free discharge of the liquidcontaminates when the device is in an inoperative position, ashereinafter described. The bore 56 of the nipple is internally threadedfor connection to a pipe for conveying away the liquid separated fromthe system. If desired, however, the entire nipple portion 54 may beomitted so that the collected liquid, when discharged by the device, maybe discharged freely directly onto the floor, or into a receptacle.

The inlet and outlet openings 20 and 22 of the body of the device arethreaded for the reception of threaded ends of pipe of the system inwhich the device is to be connected. Once the device is connected in thepiping of a system, it need not be disconnected for purposes ofservicing of the device, or replacement of any parts thereof.

When compressed air flows through the device, pressure builds up in thechamber 12, and the pressure above the piston drops, thereby permittingthe piston to move upwardly against the pressure of the spring 18, tothe position seen in Figure 2 of the drawing, thereby permitting thecompressed air to flow from the chamber 12, through the outlet opening22, to the tool, machine or apparatus being operated by compressed air.During the time compressed air is flowing through the device, liquidcontaminates are caused to collect in the sump portion of the bottommember 11. In this condition of the device, the moisture loading port 43is in registry with the sump portion of the bottom member 11, so thatliquid is permitted to flow through the port 48, into the cavity orchamber 44 of the stem 42. When the flow of air through the system isdiscontinued, the spring 18 moves the piston and stem in a downwarddirection to the position seen in Figure 1 of the drawings, where theshoulder 46 of the stem seats against the top of the sealing member 50.Such movement of the piston and stem, by the spring 18, results fromequalization of the pressure, at opposite sides of the piston, by flowof air through vent 24 in the piston. In this position of adjustment ofthe piston and stem, the loading and discharge port 48 of the stemregisters within the bore 56, of the nipple 54, so that all liquidcontained within the cavity 44 is permitted to be freely discharged.

Since devices of the type embodying the present invention areessentially used in connection with apparatus of the intermittentlyoperated type, it will be apparent that each time the flow of airthrough the device is discontinued, the liquid contained in the cavity44 of the stem is dumped or discharged, thereby continuously removingliquid contaminates from the system.

The device embodying the present invention is adapted for use in systemsof various pressures, and the device herein illustrated will performsatisfactorily in systems wherein the pressure ranges vary from to 250p.s.i. The device requires no adjustments, and automatically compensatesat any pressure range.

While in the claims reference is made to the device as being usable inconnection with compressed air lines, it is contemplated that suchlanguage be given a broad interpretation as being applicable to anysystem for handling fluids, such as steam.

Although I have herein shown and described certain preferred embodimentsof my invention, manifestly it is capable of further modification andrearrangement without departing from the spirit and scope thereof. I donot, therefore, wish to be understood as limiting this invention to theprecise embodiment herein disclosed, except as I may be so limited bythe appended claims.

I claim:

1. In a moisture extractor for a compressed air line comprising, aunitary body of inverted, cup shaped form, having a downwardly openchamber, and a piston bore at the upper end thereof, a piston movablymounted in said bore, a fluid inlet opening in said body incommunication with the chamber, a fluid outlet in said body incommunication with the piston bore and adapted to be placed incommunication with the chamber, through said bore, when the piston is inone position of adjustment, said body having a downwardly facing annularshoulder surrounding said bore, an annular screen seated at its upperend against said shoulder, a bottom member detachably connected to thelower end of the body and constituting a closure for the chamber andformed to provide a sump for collecting liquid contaminates, said memberbeing provided with a shoulder for seating against the lower end of thescreen for confining it in position, and means operable incident to areduction in pressure in said chamber for moving the piston in adownward direction, to another position of adjustment, for dischargingcollected liquid contaminates externally of said chamber.

2. In a moisture extractor for a compressed air line comprising, ahousing formed with a chamber therein,

and a piston bore opening off of said chamber, a piston movably mountedin the bore, said housing having a fluid inlet opening in communicationwith the chamber and a fluid outlet opening in communication with thepiston bore and adapted to be placed in communication with the chamber,through the bore, when the piston is in one position of adjustment, thebottom of the housing being formed to provide a sump for collectingliquid contaminates, a spring for normally urging the piston to aposition to close the communication between the outlet opening and thechamber, and an elongated stem connected at one end to the piston andthe other end being mounted for sliding movement in a guide opening inthe bottom of the housing, said stem having a liquid receiving cavitytherein and a port in open communication with the cavity, said portbeing so located as to be positioned externally of said guide opening,when the piston is in a normal inoperative position, and above the guideopening, in registration with the sump when the piston is in anoperative position, providing communication between the outlet openingand the chamber.

3. In a moisture extractor for a compressed air line comprising, ahousing formed with a chamber therein, and a piston bore opening off ofsaid chamber, a piston movably mounted in the bore, said housing havinga fluid inlet opening in communication with the chamber and a fluidoutlet opening in communication with the piston bore and adapted to beplaced in communication with the chamber, through the bore, when thepiston is in one position of adjustment, the bottom of the housing beingformed to provide a sump for collecting liquid contaminates, a springfor normally urging the piston to a position to close the communicationbetween the outlet opening and the chamber, and an elongated stemconnected at one end to the piston and the other end being mounted forsliding movement in a guide opening in the bottom of the housing, saidstem having a liquid receiving cavity therein and a port in opencommunication with the cavity, said port being so located as to bepositioned externally of said guide opening, when the piston is in anormal inoperative position, and above the guide opening, inregistration with the sump when the piston is in an operative position,providing communication between the outlet opening and the chamber, anda fluid seal positioned in the guide opening and surrounding said stem.

4. In a moisture extractor for a compressed air line comprising, ahousing formed with a chamber therein, and a piston bore opening oiI ofsaid chamber, a piston movably mounted in the bore, said housing havinga fluid inlet opening in communication with the chamber and a fluidoutlet opening in communication with the piston bore and adapted to beplaced in communication with the chamber, through the bore, when thepiston is in one position of adjustment, the bottom of the housing beingformed to provide a sump for collecting liquid contaminates, a springfor normally urging the piston to a position to close the communicationbetween the outlet opening and the chamber, an elongated stem connectedat one end to the piston and the other end being mounted for slidingmovement in a guide opening in the bottom of the housing, said stemhaving a liquid receiving cavity therein and a port in opencommunication with the cavity, said port being so located as to bepositioned externally of said guide opening, when the piston is in anormal inoperative position, and above the guide opening, inregistration with the sump when the piston is in an operative position,providing communication between the outlet opening and the chamber, anda fluid seal assembly press fitted in the bottom of the housing, aroundthe guide opening and includling a resilient O-ring surrounding saidstem.

5. In a moisture extractor for a compressed air line comprising, ahousing formed with a chamber therein and a piston bore opening 011 ofsaid chamber, a piston movably mounted in the bore, said housing havinga fluid inlet opening in communication with the chamber and a fluidoutlet opening in communication with the piston bore and adapted to beplaced in communication with the chamber, through the bore, when thepiston is in one position of adjustment, the bottom of the housing beingformed to provide a sump for collecting liquid contaminates, a springfor normally urging the piston to a position to close the communicationbetween the outlet opening and the chamber, and an elongated hollow stemthreaded at its upper end into the bottom of the piston and the otherbeing reduced in cross-section and mounted for sliding movement in aguide opening in the bottom of the housing, said reduced portionproviding a shoulder adapted to abut the bottom of the sump wall tolimit downward movement of the piston, said reduced portion of the stemhaving a port in open communication with the cavity in the stem, saidport being so located as to be positioned externally of said guideopening, when the piston is in a normal inoperative position, and abovethe guide opening, in registration with the sump when the piston is inan operative position, providing communication between the outletopening and the chamber.

References Cited in the file of this patent UNITED STATES PATENTS1,612,526 Mueller Dec. 28, 1926 2,036,106 Stuard Mar. 31, 1936 2,126,140Ross Aug. 9, 1938 2,261,026 Heigis -1 Oct. 28, 1941 2,709,524 Russell etal May 31, 1955 15 2,822,887 Engrnan Feb. 11, 1958 FOREIGN PATENTS761,397 Germany Nov. 4, 1952

